TRENTON —Gov. Chris Christie, who removed himself as a candidate for the White House just a week ago, will endorse Mitt Romney as the Republican nominee for president at a news conference in New Hampshire this afternoon, a spokesman for the Romney campaign confirmed.

Christie, who was on the way to New Hampshire, planned to join Romney, the former governor of Massachusetts, to make the announcement in Lebanon, N.H., about an hour northwest of Concord, the state capital, the Romney spokesman, Ryan Williams, said.

Christie will then accompany Romney to tonight's Republican presidential debate at Dartmouth College in in Hanover, Williams said.

New Hampshire, which holds the nation's first primary, plays a crucial role in the road to the White House. But last week Florida legislators voted to move up its primary, and New Hampshire has not settled on an earlier date.

The endorsement of Christie, who has built up a following across the country among some Tea Party activists and more moderate elements of the Republican party, is certain to buoy Romney's candidacy. Until Christie made his plans known last week, Romney's campaign was struggling to get rank-and-file Republicans and donors excited about his candidacy.

After bowing out last week, several of Christie's wealthy supporters — including Ken Langone, the co-founder of Home Depot, and Paul Singer, a hedge fund manager — announced that were shifting their allegiance, and their contributions, to Romney.

Christie's nod will undoubtedly bring more money, and expertise, to Romney campaign. New Jersey has historically been a place where presidential candidates draw significant financial support. Christie was a fundraiser for former President George W. Bush, and close friend Bill Palatucci and brother Todd Christie have a history of bundling large sums for presidential candidates.

Larry Sabato, a political analyst at the University of Virginia, said Christie's endorsement may be the rare kind of thing that can provide a tangible boost to the candidate.

He's well-liked in the Republican Party, apart from conservative hardliners who weren't going to back Romney anyway, Sabato said. In addition, Christie drew much media attention recently while considering whether to run for president himself.

"Who has been the prominent person in the last month?" Sabato said. "Not any of the announced candidates. Chris Christie."

Christie also has the potential to bring a savvy political staff to the Romney campaign , including several people who worked on Rudy Giuliani's short-lived presidential campaign in 2008 .

Mike DuHaime, who was chief strategist during Christie's gubernatorial campaign and remains a close confidant , was Giuliani's campaign manager. Bill Stepien, who currently works in the administration and was on Christie's campaign staff in 2009, was the national field director and regional campaign manager for Sen. John McCain’s in the 2008 presidential race and had previously worked for Giuliani.

Maria Comella, the current director of communications for Christie, also worked on the Giuliani and McCain campaigns.

During his news conference last week when he bowed out of the race, Christie demurred when asked whom he planned to endorse.

“If I feel like there’s somebody in the field who gives us the best chance,” he said. “I’m not in a position today to make that determination.”

Chris Christie announces he will officially not run for PresidentIn a press conference on Tuesday afternoon, New Jersey Gov. Chris Christie made it clear that he will not be seeking the presidency in 2012. He told a room full of reporters that he made his decision last night after careful consideration. (Video by Michael Monday/The Star-Ledger)

Christie has criticized the entire Republican field for not discussing the issues he thinks are most important, including Medicaid and Social Security.

Christie and Romney, who have both been Republican governors in Democratic-leaning states, share several connections. Romney endorsed Christie when he ran for governor in 2009. And in January, Romney became the first Republican contender to visit Christie at the governor's mansion in Princeton.

Then in March, Romney donated $25,000 to the New Jersey Republican Party. In addition, Christie's longtime friend, state Sen. Joseph Kyrillos (R-Monmouth), led Romney's campaign in the 2008 Republican presidential primary in New Jersey.

For months, Christie was proving that the road to the Republican nomination went through New Jersey. In addition to meeting with Romney, he held dinners at the governor's mansion in with two other governors who were considering runs: Gov. Haley Barbour of Mississippi and former Gov. Tim Pawlenty of Minnesota. He also dined with Giuliani.

Christie said this summer that he had been contacted by the campaign of Gov. Rick Perry of Texas to have a similar meeting, but neither camp has confirmed that dinner ever took place.

Perry's communications director, Ray Sullivan, said this afternoon on the Fox News program "America Live With Megyn Kelly": “Well that’s the way it works in this business sometimes, the northeast Republicans are sticking together in this case."

John Sette, chairman of the Morris County Republican Party, said he would rather be backing Christie, but that Romney was the next best choice.

Gov Chris Christie: I knew I could winResponding to a question asking if he were "too liberal" for his party, Gov. Chris Christie said that when people started attacking his politics before he got into the race, "that's when i knew I could actually win." In a press conference on Tuesday afternoon, Christie made it clear that he will not be seeking the presidency in 2012. (Video by Michael Monday/The Star-Ledger)

"He's the person with the best experience," Sette said. "It's a great move."

A poll released Monday by The Harvard and St. Anselm New Hampshire Institutes of Politics showed Romney with an 18 percentage point lead over his fellow Republican contender, Herman Cain , a former chief executive of Godfather's Pizza.

The poll also found that 70 percent of those surveyed know Christie's name, and 51 percent of people think of him favorably. Christie also had a lower unfavorable rating than any candidate officially in the race, the poll found.
Staff writers Christopher Baxter, Ginger Gibson and Chris Megerian contributed to this report.